I did some more troubleshooting and it's definitely the camera's processing crashing midway (happens more frequently after a burst).
When you take a picture, too processing is completed, the images show up as low res .jpeg.thumb files. I just did 10 pics in series and they showed up in file explorer as .jpeg.thumb. Sure enjoy, slowly all of them grew up into full jpegs, expect one, which remained .jpeg.thumb. No, I didn't open the file or anything to interrupt the processing, just saw the directory in file explorer. Now to figure out what causes processing to stop. Should be something typical, as I am seemingly the only one with this issue.
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